Miller Thunderbolt XL

[jfk92]

All,

Quick question - I don't know anything so please keep this in mind - it may be a simple as 'it says it on the cover'.

I'm looking at a couple miller thunderbolt XL units on CL. How do you tell the diff. between an AC only unit and an AC / DC unit? would there be say a "300/150" type demarcation on the cover or....say it...or an extra knob etc? For example - this poor picture posted attached....no info on it outside of the dusty picture....